This is an application for the Mentored Clinical Scientist Development Award to train Dr. Sandeep Jain. Its main educational objective is to provide Dr. Jain with the structured program necessary for him to become an independent biomedical scientist in the area of ocular neurobiology. The specific aims of the proposed educational program consist of Dr. Jain's active participation in 1) didactic graduate course work in molecular biology and neuroscience at the University of Illinois at Chicago, 2) weekly ocular cell and molecular biology seminar and conferences at the Lions of Illinois Eye Research Institute (LIERI) and other medical affiliates of the University of Illinois at Chicago, and 3) a rigorous basic science research project under the supervision of a mentoring committee comprising four established scientists and clinicians. The mentoring committee comprises role models who will provide the applicant with a supportive setting conducive to learning, an ethos and commitment to excellence as well as accountability. The long term objective of the research proposal is to help delineate some of the cornea-resident cellular (keratocyte) and molecular (EphB1/ephrinB1) nerve guidance cues that play a role in the proper growth and patterning of axons during nerve regeneration in the cornea. We propose a novel hypothesis that cornea resident keratocytes play a hitherto unrecognized role of guiding axons during regeneration of corneal nerves. The specific aims of the project are: 1) To correlate the pattern and course of EphB1/ephrinB1 expression with keratocyte activation and nerve regeneration, 2) To determine the effect of keratocyte ephrinBI ligand induced forward signaling on corneal nerve regeneration, and 3) To determine the effect of keratocyte EphB1 receptor induced forward signaling on nerve regeneration.